Recently, as a method for analyzing a component to be measured which is contained in a sample, a method for easily analyzing the kind and the amount of the component to be measured has been developed. For example, a method which has been put to practical use is a method for analyzing a specific biological molecule by a so-called sandwich assay (enzyme-linked immunosorbent assay: ELISA), in which when the component to be measured is an antigen, a capture component (an antibody) which specifically binds to the antigen is immobilized on a support base material and is reacted with a sample to be measured to conduct a certain specific binding reaction, a labeled antibody is further reacted and the label is detected.
In examples of conventional analysis methods typified by ELISA (enzyme-linked immunosorbent assay), a capture component immobilized at a reaction site and a component to be measured are reacted and a fluorescently labeled secondary capture component is specifically reacted. The concentration of the component to be measured is calculated by measuring the fluorescence intensity of the labeled capture component bound to the reaction site.